The Molecular Biology Core provides core cell biological, biochemical and molecular genetic services to the Alzheimer Disease (AD) Center and helps foster research of Emory University and outside investigators. The cell biological services provided include collecting and cataloging blood samples from well characterized patients and controls provided by the Clinical core and preparing lymphoblastoid cell lines and DNAs from these samples. They also include collecting muscle biopsies from selected patients and controls, preparing myoblast cell lines, isolating muscle mitochondria, and purifying muscle DNA. Biochemical analyses include physiological screening and mitochondrial oxidative phosphorylation (OXPHOS) enzyme analysis of ADC patients and controls. The molecular genetic analyses encompass most of the known AD genetic determinants. Patients with early onset familial AD are screened for mutations in the amyloid precursor protein (APP) gene, and tests are being developed for the recently discovered S182 and STM2 genes. For patients with late onset AD, the Molecular Biology core performs apolipoprotein E genotyping, and analysis of the a/1-antichymotrypsin alleles A and T, and the complete set of mitochondrial DNA (mtDNA) markers including the tRNA/Gln np4336G mutation. The Core also tests for markers of AD progression including somatic mtDNA rearrangement and base substitution mutations. All patient records, materials catalogued, and test results are maintained in an integrated but secure database.